Ultra-wide-angle imaging lens assembly with five lenses

ABSTRACT

An imaging lens assembly comprises a fixing diaphragm and an optical set including five lenses. An arranging order from an object side to an image side is: a first lens; a second lens; a third lens having a lens with a positive refractive power defined near the optical axis and a convex surface directed toward the image side; a fourth lens having a lens with a positive refractive power defined near the optical axis and a convex surface directed toward the image side; and a fifth lens having a concave surface with a corrugated contour directed toward the image side and disposed near the optical axis. At least one surface of the five lenses is aspheric. By the concatenation between the lenses and the adapted curvature radius, thickness, interval, refractivity, and Abbe numbers, the assembly attains a big diaphragm with ultra-wide-angle, a shorter height, and a better optical aberration.

The current application claims a foreign priority to the patentapplication of Taiwan No. 102123562 filed on Jul. 2, 2013.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an ultra-wide-angle imaging lensassembly with five lenses, in particular to a lens structure attaining abig diaphragm, a shorter height, and a high resolution by curvature,interval and optical parameter between each lens.

2. Description of the Related Art

The conventional lens structure adopts an image display lens assemblywhich is applied to smart phone, tablet PC, cell phone, notebook, andwebcam. The electronic products are developed to become lighter,thinner, shorter, and smaller and provide with higher efficiency. Avideo sensor of the image display lens assembly, such as Charge CoupledDevice (CCD) or Complementary Metal Oxide Semiconductor (CMOS), is alsodeveloped for more pixels, so the lens structure is ceaselesslydeveloped to be provided with compactness and higher resolution.

Therefore, the present invention is disclosed in accordance with anultra-wide-angle lens structure with multi-lens for a demand of thedevelopment of the image display lens assembly, especially to an imaginglens assembly of a lens structure with at least five lenses.

SUMMARY OF THE INVENTION

In view of the conventional ultra-wide-angle lens structure withmulti-lens that has big volume and lack of efficiency, anultra-wide-angle imaging lens assembly with five lenses is disclosed.

It is an object of the present invention to provide an ultra-wide-angleimaging lens assembly with five lenses, which comprises a fixingdiaphragm and an optical set. The optical set includes a first lens, asecond lens, a third lens, a fourth lens, and a fifth lens. An arrangingorder thereof from an object side to an image side is: the first lenswith a negative refractive power defined near an optical axis and aconvex surface directed toward the object side, and at least one surfaceof the first lens is aspheric; the second lens with a positiverefractive power defined near the optical axis and a convex surfacedirected toward the object side, and at least one surface of the secondlens is aspheric; the fixing diaphragm; the third lens having a lenswith a positive refractive power defined near the optical axis and aconvex surface directed toward the image side, and at least one surfaceof the third lens is aspheric; the fourth lens having a lens with apositive refractive power defined near the optical axis and convexsurfaces directed toward the image side, and at least one surface of thefourth lens is aspheric; and the fifth lens having a concave surfacewith a corrugated contour directed toward the image side and disposednear the optical axis, and at least one surface of the fifth lens isaspheric.

The imaging lens assembly satisfies the following conditionalexpression: 2.5<TL/f<3.5. The TL is defined as a distance from a toppoint of the object side of the first lens to an imaging surface side.The f is defined as a focal length of the entire lens assembly.

A shape of the aspheric surface satisfies a formula of:

$z = {\frac{{ch}^{2}}{1 + \left\lbrack {1 - {\left( {k + 1} \right)c^{2}h^{2}}} \right\rbrack^{0.5}} + {A\; h^{4}} + {Bh}^{6} + {Ch}^{8} + {Dh}^{10} + {Eh}^{12} + {Fh}^{14} + {Gh}^{16} + {Hh}^{18} + {Jh}^{20} + \ldots}$

The z is defined as a position value about a location at a height of halong a direction of the optical axis referring to a surface top point.The k is defined as a conic constant. The c is a reciprocal of a radiusof a curvature. The A, B, C, D, E, F, G, etc. are defined as high-orderaspheric surface coefficients.

The present invention is characterized in that a lens structure attainsa big diaphragm with ultra-wide-angle, a shorter height, and a highresolution by curvature, interval, and optical parameter between eachlens.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic view showing an optical structure of a firstpreferred embodiment of the present invention;

FIG. 2 is a schematic view showing a spherical aberration of the firstpreferred embodiment of the present invention;

FIG. 3 is a schematic view showing an astigmatic aberration of the firstpreferred embodiment of the present invention;

FIG. 4 is a schematic view showing a distorted aberration of the firstpreferred embodiment of the present invention;

FIG. 5 is a schematic view showing an optical structure of a secondpreferred embodiment of the present invention;

FIG. 6 is a schematic view showing a spherical aberration of the secondpreferred embodiment of the present invention;

FIG. 7 is a schematic view showing an astigmatic aberration of thesecond preferred embodiment of the present invention;

FIG. 8 is a schematic view showing a distorted aberration of the secondpreferred embodiment of the present invention;

FIG. 9 is a schematic view showing an optical structure of a thirdpreferred embodiment of the present invention;

FIG. 10 is a schematic view showing a spherical aberration of the thirdpreferred embodiment of the present invention;

FIG. 11 is a schematic view showing an astigmatic aberration of thethird preferred embodiment of the present invention;

FIG. 12 is a schematic view showing a distorted aberration of the thirdpreferred embodiment of the present invention;

FIG. 13 is a schematic view showing an optical structure of a fourthpreferred embodiment of the present invention;

FIG. 14 is a schematic view showing a spherical aberration of the fourthpreferred embodiment of the present invention;

FIG. 15 is a schematic view showing an astigmatic aberration of thefourth preferred embodiment of the present invention; and

FIG. 16 is a schematic view showing a distorted aberration of the fourthpreferred embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Before describing in detail, it should note that the like elements aredenoted by the similar reference numerals throughout disclosure.

The present invention provides an ultra-wide-angle imaging lens assemblywith five lenses, in particular to a lens structure attaining a bigdiaphragm with ultra-wide-angle, a shorter height, and a high resolutionby a curvature, an interval, an optical parameter between each lens, anda fixing diaphragm 30 disposed between a second lens 20 and a third lens40.

Referring to FIG. 1, a schematic view of an optical structure of anultra-wide-angle imaging lens assembly with five lenses is shown. Thestructure of the imaging lens comprises the fixing diaphragm 30 and anoptical set. The optical set includes a first lens 10, a second lens 20,a third lens 40, a fourth lens 50, and a fifth lens 60. An arrangingorder thereof from an object side to an image side is: the first lens 10with a negative refractive power defined near an optical axis and aconvex surface directed toward the object side, and at least one surfaceof the first lens 10 is aspheric; the second lens 20 with a positiverefractive power defined near the optical axis and a convex surfacedirected toward the object side, and at least one surface of the secondlens 20 is aspheric; the fixing diaphragm 30; the third lens 40 having alens with a positive refractive power defined near the optical axis anda convex surface directed toward the image side, and at least onesurface of the third lens 40 is aspheric; the fourth lens 50 having alens with a positive refractive power defined near the optical axis andconvex surfaces directed toward the image side, and at least one surfaceof the fourth lens 50 is aspheric; the fifth lens 60 having a concavesurface with a corrugated contour directed toward the image side anddisposed near the optical axis, and at least one surface of the fifthlens 60 is aspheric; a filter unit 70 filtering light with specific wavelength and adopted by an infrared stopping filter unit applied to avisible light image; and an image sensor 80 (an imaging surface side)used for receiving a digital signal transformed by an infrared invisiblelight image of the filter.

The imaging lens assembly satisfies the following conditionalexpression: 2.5<TL/f<3.5. The TL is defined as a distance from a toppoint of the object side of the first lens to the imaging surface side.The f is defined as a focal length of the entire lens assembly.

The first lens 10 includes a first surface 11 facing an object side anda second surface 12 facing the imaging surface side. The first surface11 is defined as a convex surface disposed near the optical axisopposite to the object side. The second surface 12 is defined as aconcave surface disposed near the optical axis opposite to the imagingsurface side. The second lens 20 includes a third surface 21 facing theobject side and a fourth surface 22 facing the imaging surface side. Thethird surface 21 is defined as a convex surface disposed near theoptical axis opposite to the object side. The fourth surface 22 isdefined as a concave surface disposed near the optical axis opposite tothe imaging surface side. The third lens 40 includes a fifth surface 41facing the object side and a sixth surface 42 facing the imaging surfaceside. The fifth surface 41 is defined as a convex surface disposed nearthe optical axis opposite to the object side. The sixth surface 42 isdefined as a convex surface disposed near the optical axis opposite tothe imaging surface side. The fourth lens 50 includes a seventh surface51 facing the object side and an eighth surface 52 facing the imagingsurface side. The seventh surface 51 is defined as a convex surfacedisposed near the optical axis opposite to the object side. The eighthsurface 52 is defined as a convex surface disposed near the optical axisopposite to the imaging surface side. The fifth lens 60 includes a ninthsurface 61 facing the object side and a tenth surface 62 facing theimaging surface side. The ninth surface 61 is defined as a concavesurface disposed near the optical axis opposite to the object side. Thetenth surface 62 is defined as a concave surface disposed near theoptical axis opposite to the imaging surface side. At least one surfaceof the first lens 10, the second lens 20, the third lens 40, the fourthlens 50, and fifth lens 60 is aspheric, thereby correcting the sphericalaberration and the image aberration for having a characteristic of lowtolerance sensitivity.

A shape of the aspheric surface of the imaging lens assembly satisfies aformula of:

$z = {\frac{{ch}^{2}}{1 + \left\lbrack {1 - {\left( {k + 1} \right)c^{2}h^{2}}} \right\rbrack^{0.5}} + {A\; h^{4}} + {Bh}^{6} + {Ch}^{8} + {Dh}^{10} + {Eh}^{12} + {Fh}^{14} + {Gh}^{16} + {Hh}^{18} + {Jh}^{20} + \ldots}$

The z is defined as a position value about a location at a height of halong a direction of the optical axis referring to a surface top point.The k is defined as a conic constant. The c is a reciprocal of a radiusof a curvature. The A, B, C, D, E, F, G, etc. are defined as high-orderaspheric surface coefficients.

In an ultra-wide-angle micro-optical image capturing device of thepresent invention, the fixing diaphragm 30 is disposed between theobject and the third lens 40 for getting an incident beam. The firstlens 10 is adopted by a lens with a negative refractive power definednear the optical axis and the second lens 20, the third lens 40, and thefourth lens 50 are adopted by lenses with a positive refractive powerdefined near the optical axis. The first lens 10 adopts the firstsurface 11 convexly defined toward the object side and disposed near theoptical axis for assembling the external incident beam withultra-wide-angle and keeping the beam on the second surface 12 of thefirst lens 10, thereby presenting a function of the aspheric surface,correcting the aberration, reducing the tolerance sensitivity, andrendering the device have ultra-wide-angle with an image-capture angleover 100°. The third surface 21 defined on the second lens 20 as aconvex surface disposed near the optical axis opposite to the objectside is then expanded. The fourth surface 22 is defined as a lens with apositive refractive power and a concave surface disposed near theoptical axis opposite to the imaging surface side. The fourth lens 50radiates via the seventh surface 51 that is concavely defined toward theimaging surface side and disposed near the optical axis, so that thebeam is able to be spread on the tenth surface 62 of the fifth lens 60with a larger dimension. That is to say, the incident beam is expandedby the third surface 21 for being spread on the tenth surface 62 with alarger dimension, thereby presenting the function of aspheric surface,correcting the aberration, and reducing tolerance sensitivity.

The aspheric surface not only corrects the spherical aberration and theimage aberration but also includes the fixing diaphragm 30 disposedbetween the second lens 20 and the third lens 40, thereby reducing thefull length of the lens optical system. The first lens 10, the secondlens 20, the third lens 40, the fourth lens 50, and the fifth lens 60are preferably adopted by plastic, which is conducive to eliminate theaberration and reduce the weight of the lens. The entire optical systemconsists of five plastic lenses and benefits a mass production. Theoptical system also provides with the low tolerance sensitivity to meeta requirement of the mass production. The filter unit 70 used forfiltering infrared invisible light and allowing visible light forms anultra-wide-angle micro-optical image capturing device capable ofcapturing the sight that people see.

By the concatenation between the above-mentioned surfaces of lenses andthe adapted curvature radius, thickness, interval, refractivity, andAbbe numbers, the assembly attains a big diaphragm withultra-wide-angle, a shorter height, and a better optical aberration.

First Preferred Embodiment of the Present Invention

Due to the above-mentioned technique of the present invention, it isable to be practiced in accordance with the following values:

Basic lens data of the first preferred embodiment Thick Curva- ness/ture Interval Refrac- Abbe radius (Thick- tivity number Surfaces(Radius) ness) (Nd) (Vd) First First 19.5 0.26 1.544100 56.093602 lenssurface 10 11 Second 0.97 0.35 surface 12 Second Third 0.78 0.471.635500 23.891420 lens surface 20 21 Fourth 1.08 0.17 surface 22 Fixingdiaphragm 30 ∞ −0.02 Third Fifth 2.98 0.67 1.544100 56.093602 lenssurface 40 41 Sixth −1.99 0.07 surface 42 Fourth Seventh 1.90 0.681.544100 56.093602 lens surface 50 51 Eighth −0.57 0.11 surface 52 FifthNinth −1.14 0.25 1.635500 23.891420 lens surface 60 61 Tenth 1.31 0.17surface 62 Filter Eleventh ∞ 0.3 1.516800 64.167336 unit surface 70 71Twelfth ∞ 0.28 surface 72

The filter unit 70 has a thickness of 0.3 mm and is adopted by aninfrared stopping filter unit. A wave length of the light passingtherethrough is 450-650 mm.

A shape of the above-mentioned aspheric surface satisfies the followingformula:

$z = {\frac{{ch}^{2}}{1 + \left\lbrack {1 - {\left( {k + 1} \right)c^{2}h^{2}}} \right\rbrack^{0.5}} + {A\; h^{4}} + {Bh}^{6} + {Ch}^{8} + {Dh}^{10} + {Eh}^{12} + {Fh}^{14} + {Gh}^{16} + {Hh}^{18} + {Jh}^{20} + \ldots}$

The z is defined as a position value about a location at a height of halong a direction of the optical axis referring to a surface top point.The k is defined as a conic constant. The c is a reciprocal of a radiusof a curvature. The A, B, C, D, E, F, G etc. are defined as high-orderaspheric surface coefficients.

The values of quadratic surface coefficient of the aspheric surface ofthe first preferred embodiment are listed as follows:

The first surface 11 (k=−99):

A: 0.120860

B: −0.043532

C: 0.024980

D: −0.008249

E: 0.001732

F: 0.000000

G: 0.000000

The second surface 12 (k=−1.12):

A: −0.270255

B: 0.366500

C: −0.243760

D: 0.054755

E: 0.000000

F: 0.000000

G: 0.000000

The third surface 21 (k=−0.86):

A: −0.256389

B: −0.002088

C: 0.646003

D: −0.790538

E: 0.000000

F: 0.000000

G: 0.000000

The fourth surface 22 (k=3.63):

A: 0.003768

B: 0.776136

C: −1.322913

D: 26.150389

E: −0.000185

F: 0.000000

G: 0.000000

The fifth surface 41 (k=−71.92):

A: 0.253812

B: 1.588127

C: −19.307721

D: 76.868704

E: 2.378378e-013

F: 0.000000

G: 0.000000

The sixth surface 42 (k=−104.03):

A: −2.222512

B: 4.950060

C: −14.441919

D: 18.218801

E: 0.000000

F: 0.000000

G: 0.000000

The seventh surface 51 (k=0.00):

A: −0.623089

B: −0.269938

C: −0.310977

D: −2.024637

E: 0.000000

F: 0.000000

G: 0.000000

The eighth surface 52 (k=−5.26):

A: 0.642975

B: −2.022728

C: 1.131730

D: −0.181891

E: 0.000000

F: 0.000000

G: 0.000000

The ninth surface 61 (k=−29.61):

A: 0.351190

B: −3.811852

C: 4.918355

D: −2.252320

E: −0.502655

F: 0.832491

G: 0.000000

The tenth surface 62 (k=0.00)

A: −0.731992

B: 0.178817

C: 0.004144

D: 0.032295

E: −0.056005

F: 0.015918

G: 0.000000

According to the above-mentioned values, the related exponent ofperformance of the micro-image capturing lens is: f=1.296 mm; TL=3.76mm; TL/f=2.90.

Referring to FIG. 2, a schematic view of a spherical aberration of thefirst preferred embodiment of the present invention is shown. Referringto FIG. 3, a schematic view of an astigmatic aberration of the firstpreferred embodiment of the present invention is shown. Referring toFIG. 4, a schematic view of a distorted aberration of the firstpreferred embodiment of the present invention is shown. The measuredastigmatic aberration, distorted aberration, and spherical aberrationare in the standard scope and have a good optical performance andimaging quality according to the above-mentioned figures.

Second Preferred Embodiment of the Present Invention

Due to the above-mentioned technique of the present invention, it isable to be practiced in accordance with the following values:

Basic lens data of the second preferred embodiment Thick Curva- ness/ture Interval Refrac- Abbe radius (Thick- tivity number Surfaces(Radius) ness) (Nd) (Vd) First First 2.95 0.28 1.514600 57.17778 lenssurface 10 11 Second 0.80 0.11 surface 12 Second Third 1.14 0.581.635500 23.891420 lens surface 20 21 Fourth 1.38 0.21 surface 22 Fixingdiaphragm 30 ∞ 0.01 Third Fifth 4.24 0.49 1.514600 57.17778 lens surface40 41 Sixth −0.68 0.22 surface 42 Fourth Seventh −0.68 0.33 1.54410056.093602 lens surface 50 51 Eighth −0.64 0.14 surface 52 Fifth Ninth1.81 0.62 1.544100 56.093602 lens surface 60 61 Tenth 1.40 0.20 surface62 Filter Eleventh ∞ 0.3 1.516800 64.167336 unit surface 70 71 Twelfth ∞0.25 surface 72

The filter unit 70 has a thickness of 0.3 mm and is adopted by aninfrared stopping filter unit. A wave length of the light passingtherethrough is 450-650 mm.

The values of quadratic surface coefficient of the aspheric surface ofthe second preferred embodiment are listed as follows:

The first surface 11 (k=−8.09):

A: −0.076364

B: 0.052546

C: 0.020178

D: −0.024610

E: 0.007741

F: 0.000000

G: 0.000000

The second surface 12 (k=−0.17):

A: −0.114338

B: −0.482088

C: −0.006313

D: 0.098751

E: −0.243835

F: 0.000000

G: 0.000000

The third surface 21 (k=−0.36):

A: 0.486100

B: −0.150616

C: 0.378690

D: 0.979435

E: −1.427587

F: 0.000000

G: 0.000000

The fourth surface 22 (k=0.87):

A: 1.591932

B: −1.186978

C: 39.642648

D: −66.463202

E: −3.229075e-005

F: 0.000000

G: 0.000000

The fifth surface 41 (k=−98.81):

A: 0.032717

B: 0.777552

C: −23.946204

D: 4.880313

E: −6.788012e-011

F: 0.000000

G: 0.000000

The sixth surface 42 (k=0.62):

A: 0.654822

B: 0.046021

C: −6.859322

D: 17.213693

E: 0.000000

F: 0.000000

G: 0.000000

The seventh surface 51 (k=0.00):

A: 2.266994

B: −4.190758

C: 8.167473

D: −5.982716

E: 0.000000

F: 0.000000

G: 0.000000

The eighth surface 52 (k=−2.68):

A: 0.030632

B: −1.016005

C: 3.782609

D: −2.510238

E: 0.000000

F: 0.000000

G: 0.000000

The ninth surface 61 (k=−3.77)

A: −0.312190

B: −0.883667

C: 1.030004

D: −0.418662

E: −0.845494

F: 1.058650

G: 0.000000

The tenth surface 62 (k=0.00):

A: −0.468743

B: 0.245303

C: −0.261756

D: 0.117260

E: −0.008273

F: −0.008623

G: 0.000000

According to the above-mentioned values, the related exponent ofperformance of the micro-image capturing lens is: f=1.259 mm; TL=3.75mm; TL/f=2.98.

Referring to FIG. 6, a schematic view of a spherical aberration of thesecond preferred embodiment of the present invention is shown. Referringto FIG. 7, a schematic view of an astigmatic aberration of the secondpreferred embodiment of the present invention is shown. Referring toFIG. 8, a schematic view of a distorted aberration of the secondpreferred embodiment of the present invention is shown. The measuredastigmatic aberration, distorted aberration, and spherical aberrationare in the standard scope and have a good optical performance andimaging quality according to the above-mentioned figures.

Third Preferred Embodiment of the Present Invention

Due to the above-mentioned technique of the present invention, it isable to be practiced in accordance with the following values:

Basic lens data of the third preferred embodiment Thick- Curva- ness/ture Interval Refrac- Abbe radius (Thick- tivity number Surfaces(Radius) ness) (Nd) (Vd) First First 19.5 0.26 1.544100 56.093602 lenssurface 10 11 Second 0.97 0.34 surface 12 Second Third 0.80 0.511.635500 23.891420 lens surface 20 21 Fourth 1.10 0.18 surface 22 Fixingdiaphragm 30 ∞ −0.02 Third Fifth 2.74 0.64 1.544100 56.093602 lenssurface 40 41 Sixth −1.73 0.09 surface 42 Fourth Seventh 1.98 0.661.544100 56.093602 lens surface 50 51 Eighth −0.62 0.11 surface 52 FifthNinth −1.29 0.25 1.635500 23.891420 lens surface 60 61 Tenth 1.28 0.16surface 62 Filter Eleventh ∞ 0.3 1.516800 64.167336 unit surface 70 71Twelfth ∞ 0.28 surface 72

The filter unit 70 has a thickness of 0.3 mm and is adopted by aninfrared stopping filter unit. A wave length of the light passingtherethrough is 450-650 mm.

The values of quadratic surface coefficient of the aspheric surface ofthe third preferred embodiment are listed as follows:

The first surface 11 (k=−99.00):

A: 0.130411

B: −0.048831

C: 0.029435

D: −0.009632

E: 0.001812

F: 0.000000

G: 0.000000

The second surface 12 (k=−1.20):

A: −0.263159

B: 0.388136

C: −0.248846

D: 0.055115

E: 0.000000

F: 0.000000

G: 0.000000

The third surface 21 (k=−0.98):

A: −0.285573

B: 0.052920

C: 0.420778

D: −0.239140

E: 0.000000

F: 0.000000

G: 0.000000

The fourth surface 22 (k=4.18):

A: −0.112307

B: 0.704359

C: −2.495231

D: 25.597552

E: −0.000185

F: 0.000000

G: 0.000000

The fifth surface 41 (k=−36.93):

A: 0.118304

B: 0.840681

C: −10.241149

D: 36.590378

E: 2.695598e-013

F: 0.000000

G: 0.000000

The sixth surface 42 (k=−13.70):

A: −1.726404

B: 2.135053

C: −6.597376

D: 9.068656

E: 0.000000

F: 0.000000

G: 0.000000

The seventh surface 51 (k=0.00):

A: −0.848774

B: 0.389382

C: −2.197055

D: −0.133761

E: 0.000000

F: 0.000000

G: 0.000000

The eighth surface 52 (k=−6.49):

A: 0.444448

B: −2.133344

C: 1.450184

D: −0.252467

E: 0.000000

F: 0.000000

G: 0.000000

The ninth surface 61 (k=−36.35):

A: 0.145604

B: −3.714141

C: 4.606180

D: −1.813766

E: −0.502655

F: 0.832491

G: 0.000000

The tenth surface 62 (k=0.00):

A: −0.819487

B: 0.253437

C: −0.037115

D: 0.021567

E: −0.045731

F: 0.016789

G: 0.000000

According to the above-mentioned values, the related exponent ofperformance of the micro-image capturing lens is: f=1.30 mm; TL=3.76 mm;TL/f=2.89.

Referring to FIG. 10, a schematic view of a spherical aberration of thethird preferred embodiment of the present invention is shown. Referringto FIG. 11, a schematic view of an astigmatic aberration of the thirdpreferred embodiment of the present invention is shown. Referring toFIG. 12, a schematic view of a distorted aberration of the thirdpreferred embodiment of the present invention is shown. The measuredastigmatic aberration, distorted aberration, the spherical aberrationare in the standard scope and have a good optical performance andimaging quality according to the above-mentioned figures.

Fourth Preferred Embodiment of the Present Invention

Due to the above-mentioned technique of the present invention, it isable to be practiced in accordance with the following values:

Basic lens data of the fourth preferred embodiment Thick- Curva- ness/ture Interval Refrac- Abbe radius (Thick- tivity number Surfaces(Radius) ness) (Nd) (Vd) First lens First 6.32 0.28 1.514600 57.17778 10surface 11 Second 0.69 0.06 surface 12 Second Third 1.01 0.68 1.63550023.891420 lens 20 surface 21 Fourth 1.85 0.24 surface 22 Fixingdiaphragm 30 ∞ ∞ 0.00 Third lens Fifth 3.36 0.51 1.514600 57.17778 40surface 41 Sixth −0.67 0.23 surface 42 Fourth Seventh −0.66 0.311.534611 56.072163 lens 50 surface 51 Eighth −0.67 0.06 surface 52 Fifthlens Ninth 1.48 0.63 1.544100 56.093602 60 surface 61 Tenth 1.37 0.18surface 62 Filter Eleventh ∞ 0.3 1.516800 64.167336 unit 70 surface 71Twelfth ∞ 0.28 surface 72

The filter unit 70 has a thickness of 0.3 mm and is adopted by aninfrared stopping filter unit. A wave length of the light passingtherethrough is 450-650 mm.

The values of quadratic surface coefficient of the aspheric surface ofthe fourth preferred embodiment are listed as follows:

The first surface 11 (k=−99.00):

A: 0.006972

B: −0.007745

C: 0.018949

D: −0.008813

E: 0.001611

F: 0.000000

G: 0.000000

The second surface 12 (k=−0.56):

A: −0.252410

B: −0.273865

C: −0.091714

D: 0.058115

E: 0.021166

F: 0.000000

G: 0.000000

The third surface 21 (k=−0.51):

A: 0.152876

B: 0.211828

C: −0.332151

D: 1.046094

E: −0.786177

F: 0.000000

G: 0.000000

The fourth surface 22 (k=4.67):

A: 1.089271

B: 2.607324

C: −3.852920

D: 68.379090

E: −3.229066e-005

F: 0.000000

G: 0.000000

The fifth surface 41 (k=−47.35):

A: 0.028983

B: −1.366025

C: 1.640750

D: −103.018927

E: −1.878362e-012

F: 0.000000

G: 0.000000

The sixth surface 42 (k=0.56):

A: 0.535304

B: 0.319529

C: −6.568534

D: 15.800973

E: 0.000000

F: 0.000000

G: 0.000000

The seventh surface 51 (k=0.00):

A: 2.271573

B: −3.829659

C: 6.576384

D: −3.872465

E: 0.000000

F: 0.000000

G: 0.000000

The eighth surface 52 (k=−1.02):

A: 0.354082

B: −0.314642

C: 2.216538

D: −1.938111

E: 0.000000

F: 0.000000

G: 0.000000

The ninth surface 61 (k=−13.37):

A: −0.499153

B: −0.313673

C: 0.508271

D: −0.353739

E: −0.181652

F: 0.547204

G: 0.000000

The tenth surface 62 (k=0.00):

A: −0.612448

B: 0.424141

C: −0.330009

D: 0.082335

E: 0.034274

F: −0.021202

G: 0.000000

According to the above-mentioned values, the related exponent ofperformance of the micro-image capturing lens is: f=1.159 mm; TL=3.75mm; TL/f=3.24.

Referring to FIG. 14, a schematic view of a spherical aberration of thefourth preferred embodiment of the present invention is shown. Referringto FIG. 15, a schematic view of an astigmatic aberration of the fourthpreferred embodiment of the present invention is shown. Referring toFIG. 16, a schematic view of a distorted aberration of the fourthpreferred embodiment of the present invention is shown. The measuredastigmatic aberration, distorted aberration, the spherical aberrationare in the standard scope and have a good optical performance andimaging quality according to the above-mentioned figures.

The micro-optical image capturing device utilizes a plurality ofaspheric surface lens with five lenses, the front four lens of whichhave refractive power defined near the optical axis sequentiallyarranged as negative, positive, positive, and positive, and the filterunit 70 which filters a light with infrared wave length and allows thevisible light with the demanded wave length. The filter unit 70 ispreferably adopted by an infrared stopping filter unit applied to thevisible light image.

By making use of the aspheric surface that corrects the aberration,reduces the tolerance sensitivity, and includes the fixing diaphragm 30disposed between the second lens 20 and the third lens 40, not only theaberration is corrected but also the full length of the lens opticalsystem is reduced. Further, the device provides with an ultra-wide-anglewith an image capturing angle over 100°. The first, second, third,fourth, and fifth lenses are preferably adopted by plastic, which isconducive to eliminate the aberration and reduce the weight of the lens.The entire optical system consists of five plastic lenses and provideswith the low tolerance sensitivity. The optical system is also easy tobe manufactured and assembled and benefits a mass production.Furthermore, the optical system provides with a good imaging quality tomeet the requirement of miniaturizing the portable image capturingproducts.

While we have shown and described the embodiment in accordance with thepresent invention, it should be clear to those skilled in the art thatfurther embodiments may be made without departing from the scope of thepresent invention.

I claim:
 1. An ultra-wide-angle imaging lens assembly with five lensescomprising a fixing diaphragm and an optical set; said optical setincluding a first lens, a second lens, a third lens, a fourth lens, anda fifth lens, an arranging order thereof from an object side to an imageside being: said first lens having a negative refractive power definednear an optical axis and a convex surface directed toward said objectside; at least one surface of said first lens being aspheric; saidsecond lens having a positive refractive power defined near said opticalaxis and a convex surface directed toward said object side; at least onesurface of said second lens being aspheric; said fixing diaphragm; saidthird lens having a lens with a positive refractive power defined nearsaid optical axis and a convex surface directed toward said image side;at least one surface of said third lens being aspheric; said fourth lenshaving a lens with a positive refractive power defined near said opticalaxis and a convex surface directed toward said image side; at least onesurface of said fourth lens being aspheric; and said fifth lens having aconcave surface with a corrugated contour directed toward said imageside and disposed near said optical axis; at least one surface of saidfifth lens being aspheric.
 2. The ultra-wide-angle imaging lens assemblywith five lenses as claimed in claim 1 further satisfying the followingexpression: 2.5<TL/f<3.5, wherein said TL is defined as a distance froma top point of said object side of said first lens to an imaging surfaceside, and said f is defined as a focal length of said entire lensassembly.